James w



' (No Model.)

J. W. MSDONOUGH.

' TELEPHONE.

No. 245,534. PatentedAug. 9,1881.

WITNESSES; INVENTOR:

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N4 PETERS. PhclwLilhogrlphor. Wa

U iTe r STATES ATJENT OFFICE.

- JAMES \V. MGDONOUGH, OF CHICAGO, ILLINOIS, ASSIGNOR TO LOGAN C. MURRAY, OF NEIV YORK.

TELEPl-lONE.

SPECIFICATION forming part of Letters Patent No. 245,534, dated August 9, 1881.

Application filed May 27, 1881.

To all whom it may concern Be it known that I, JAMES W. MODONOUGH, of the city of Chicago, in the county of Cook, State of Illinois, have invented a new and useful Telephone, for which I made an application for patent April 10, 1876; and I do hereby declare the following to be a full, clear, and exact description thereof, which will enable others skilled in the art to which my invention appertains to make and use the same, reference being had to the accompanying drawings.

The general object of my invention, as I have setforthin my original application and in other divisions thereof tiled of even date with this division, is to provide a means for transmitting articulate sounds from one place to another through the medium of electricity; but the part of my invention to which this present division of my said application appertains consists in a. certain combination of mechanism constituting a receiving apparatus specifically set forth in the claim at the end of this schedule.

In other divisions of my said application of April 1t), 1876, filed at an even date withthis present one, I have specified and claimed other combinations or subj cot-matter, which, so far as this division is concerned, are not here claimed, but are specified at the end of this schedule.

In order that persons skilled in the art may understand, make, and use my present invention, I will proceed to describe the manner in which I have constructed and combined it with other parts in a speaking-telephone apparatus.

Figure 1 represents a perspective view of a telephone receiving apparatus embodying my invention joined in circuit with my telephonetra-nsmitter. Fig. 2 represents a sectional plan of the same, taken on line :10 w, drawn across Fig. 1. Fig. 3 represents a vertical transverse section of the telephone-transmitter, taken on line y y; and Fig. 4 represents ageneral plan or top view of the same.

Like letters of reference represent like parts.

In the drawings, A represents the transmitting membrane or apparatus, composed of vellum or any suitable material that is sensitive to the vibrations of sound, which is stretched upon a metal hoop or band, a, permanently attached to the bed A by an gle-pieces T, Fig. l.

C C are metal plates, of German silver or (No model.)

such like material, attached to the upper surface of the membrane A, each side of its center or point of greatest range of vibration and insulated from each other. D is a metal bolt permanently attached at its lower end to said membrane A, centrally between plates C C and insulated from them.

v D is the circuit-controller, which consists of an arch-shaped piece of German silver or like material, loosely secured atits center upon the bolt 1), and bent upward at each end from the membrane A, as shown in Fig. 3, so as to form depending V-shaped legs, adapted to rest upon the respective plates C C and to make contact between part of their granular surfaces and the granular surfaces of the controller in the manner set forth in the several divisions of my original application relating to the transmitter.

F is the receiving or sounding membrane, which is also composed of vellum or any suitable material that is sensitive to the vibrations of sound, and is stretched upon a metal hoop or band, a, secured to the side frame, G, of wood or such like insulating material, of the receiving or sounding apparatus, as shown in Fig. 1.

G is the magnet, of a continuous piece of iron, surrounded by a helix of insulated wire, and connected to the instrument immediately in front of the membrane F and at a point near its center.

H is a thin metal armature-plate permanently attached to and supported by the membrane F between it and the magnet, as shown in Fig. 1, so that the membrane receives the exact and entire motion of its whole'area.

R is a sound-recess in the frame or holder of the receiver inclosed on its sides or circumference by the wood of the frame G and on the end near the magnet by the membrane, so that the sounds emitted by the armature and membrane may be confined and directed to the ear of the listener, while all exterior sounds are excluded.

To each of the plates C C is connected a wire, J, one of which is connected with the battery K, and the other with the ground-wire L. To each of the poles of the magnet is connected a wire, M, one of which is connected with the battery K, and the other to the groundwire, as shown in Fig. 1, by means of connecting-screws N N, mounted or fixed in the wooden frame at the same end with the magnet and insulated therefrom and from one another by the material of the holder.

The operation of my telephone-receiving apparatus is as follows: The transmitting-membrane being at rest, the circuit-controller rests upon the plates and completes the circuit of the electric battery through the helix of the receiving apparatus. The said membrane being sensitive to sound-vibrations produced in its vicinityis made to vibrate thereby, and the flow of the electricity through the wires and the helix is thereby controlled by the action of the circuit-controllerDresting upon the plates 0 C. By these means the magnet G is caused to alternately attract and release the armature H, causing it and the membrane F to vibrate in response to the action of the transmitter when affected by sound waves or vibrations.

Having now fully described my invention of a telephone receiving apparatus, as shown and set forth in the drawings and specification filed in the Patent Office April 10, 1876, I wish itto be understood that in this present division of my application I make no claim to the telephone transmitting apparatus, that being here shown merely to indicate the manner of using my telephone receiver, nor do 1 make any broad claim to my receiver. In this present division I do not therefore claim the subjectmatter claimed in the other divisions of my original application filed ofeven date with this present division, which claims are as follows:

1. A tele1 )hone-receiver consisting of the combination,in an electric circuit,of a magnet and a diaphragm, supported and arranged in close proxi mity thereto,whereby sounds thrown upon the line may be reproduced accurately as to pitch and quality, substantially in the manner hereinbefore set forth.

2. The combination, substantially as here inbefore set forth, of a transmitting-membrane composed of vellum or any suitable material that is sensitive to the vibrations of sound, and a piece or pieces of conducting material connected with the same, and receiving from it vibrations less in extent than its extreme range of vibration with a circuit-controller, whieh,when at rest, has points of contact with said conducting piece or pieces, making part of an electric circuit through them and the battery, and which receives from the membrane when in motion said reduced vibrations in accord with the waves of air-producing sound, and thereby causes impulses in the electric current through the said conducting piece or pieces, all constructed and operating substantially in the manner described.

3. The combination, substantially as hereinbefore setforth,of a transmitting-membrane composed of vellum or any suitable material that is sentitive to the vibrations of sound, and a circuit-controller arranged to vibrate in connection with it, and a conducting piece or pieces, wires, and a battery with the magnet, helix, armature, and membrane of the receiving apparatus, whereby vibrations are caused in said armature and membrane by means of an electric current, substantially in the manner and for the purposes set forth.

4. Broadly, the art of transmitting articulate speech by electricity.

5. Broadly, a variable-resistancecontact transmitter for electro-speakin g telephones.

6. Broadly, a magneto-receiver for electrospeaking telephones.

7. The combination, substantially as hereinbefore set forth, of a transmitting-membrane composed of vellum or any suitable material that is sensitive to the vibrations of sound, and a piece or pieces of conducting material receiving motion from the same, and a circuitcontroller provided with means for adjustablycontrolling its vibrations in relation to said plate or plates and membrane, substantially as described.

What I do claim in this division as part of my whole invention, and desire to secure by Letters Patent, is-- The combination, substantially as hereinbefore set forth, for a telephone-receiving apparatus, of a helix-and magnet, and connectingpost to which the wires of the helix arejoined, mounted in one end of a frame or holder of Wood or such like insulating material; a membrane mounted on the opposite end of said frame or holder, a portion of the face of which membrane presents a material, attached to and supported wholly thereby, capable of being attracted by the magnet and in close proximity thereto, so that the said membrane shall be caused to vibrate by the action of pulsations in an electric current in the helix around the magnet with a sound recess at the opposite side of the membrane from the magnet to confine the sounds received therein and exclude exterior sounds from the ear of the listener, and adapted at the same time to allow the ear of the listener-to be placed in close proximity to the membrane, all constructed and arranged to operate substantially in the manner de' scribed.

JAMES W. MODONOUGH.

\Vitnesses Josnrrr A. SMlTH, W. L. BENNEM.

Correction in Letters Patent No 245,534,,

It is hereby certified'that-in Letters Patent No. 245,534, issued August 9, 1881 to Logan (J. Murray, assignee ofJanies W. M cDonough,for an improvementin Telephones,

errors occur in lines 57 9'6, and 107 on page 2 of the printed specification forming apart of said Letters Patent, requiring correction as follows: in line 57, after the Word air strike out the hyphen and insert a comma; in line 96, for post read posts, in line 107, after the word. nagtgnefli insert a comma; that the proper corrections have been -made in' the files and records of the Patent Ofiice, and are hereby made in said Letters Patent. H Signed, countersigued, u-iulsealctl this 13th day of September, A. D. 1881.

, [SEAL] I A. BELL,

Acting Secretary of the Interior. Oountersigned I E. M. MARBLE, 

